The invention relates to the compensation for the torque produced by the main rotor of a helicopter.
For the purpose of torque compensation in helicopters, use is conventionally made of axial fans, in the form of tail rotors, to compensate for the torque produced by the main rotor. Here, the tail rotor attached to the tail boom of the helicopter produces a thrust which is directed horizontally, that is as far as possible perpendicular to the vertical axis, in order to counteract the turning of the fuselage about the vertical axis.
Tail rotors of this type are predominantly arranged unshrouded on the boom, and thus present a safety risk, for example for people on the ground. For the purpose of solving this problem and other disadvantages of unshrouded tail rotors, an enclosed tail rotor is proposed in DE 102008015073 A1, a so-called Fenestron (fan tail), with which not only can the safety risk be lowered but also, for example, the noise generation and vibrations can be reduced, because the tips of the blades do not circulate in the open.
However, a disadvantageous effect is that the shrouding results in a higher weight and higher construction costs. Furthermore, such types of tail rotors are comparatively small in size, which does however have the consequence that a higher energy requirement arises for the torque compensation.